The present invention relates to the production of market pulp. More particularly, methods and systems are provided for producing market pulp which include treatment of pulp with diverse ionic compounds before pulp drying.
In the pulp making industry, cellulose-containing feed material has been defibrated chemically, mechanically, or both, and then typically is washed and at least partly dewatered after such operations. In pulping processes in which the pulp is chemically treated, such as by chemical digestion, bleaching, or other chemical treatments, dewatering can be used to drain water and separate free chemical from the fibers. Some pulp mills may be integrated with a paper making plant, wherein the dewatering of the product pulp may be limited such that slurry pulp or wet laid pulp can be directly advanced to a papermaking machine at the same production site. Other pulp mills produce market pulp in non-integrated production operations. Market pulp can be pulp product which has been significantly dewatered in the final stages of pulp processing. Market pulp further may be formed into bales or rolls of dewatered pulp. The market pulp can be transported to other locations for later use.
The present investigators have realized that the rate at which pulp dewatering can be accomplished in a pulp mill in the production of market pulp can significantly affect the overall line speed and production capacity of the pulp mill or similar production facility. The present investigators have realized that there is a need for new methods and systems for producing market pulp with enhanced pulp-dewatering performance and efficiencies.